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V12.6 Radar Legends (When from Internet) Weather Legends in FOREFLIGHT MOBILE 17th Edition Covers ForeFlight Mobile v12.6 Radar Legends (when from Internet) Snowy/Icy Precipitation Mixed Precipitation Rain Echo top (in 100’s of feet) ex: 24,900’ Storm Track Estimated position in 20, 40 and 60 minutes ForeFlight Mobile Legends v12.6 and later! 2 Rain - Radar Intensity (dBZ) vs. Color Based on RGB values assigned to dBZ range(s) dBZ Internet Color1 ADS-B Color2,4 SiriusXM Color3 5 none shown 10 none shown 15 20 25 30 35 40 45 50 55 60 65 70 75 95 1. Colors are interpolated between levels when rendered on an image. 2. ADS-B (FIS-B) NEXRAD radar is displayed with 6 intensity ranges. 3. Some dBZ intensity/color divisions do not fall exactly on 5 dBZ lines, so are shown as close as possible to specification. ForeFlight Mobile Legends v12.6 and later! 3 Mixed Rain/Snow - Radar Intensity (dBZ) vs. Color Based on RGB values assigned to dBZ range(s) dBZ Internet Color1 ADS-B Color2,3,5 SiriusXM Color4 5 none shown 10 none shown 15 20 25 30 35 40 45 50 55 60 65 70 75 1. Colors are interpolated between levels when rendered on an image. 2. ADS-B (ie: FIS-B) NEXRAD radar is displayed with 6 intensity ranges. 3. FIS-B NEXRAD doesn't include precipitation type, so "Mixed" is displayed at the same reflectivity colors as rain. See AIM Chapter 7: http://tfmlearning.fly.faa.gov/ publications/atpubs/aim/chap7/aim0701.html 4. Some dBZ intensity/color divisions do not fall exactly on 5 dBZ lines, so are shown as close as possible to specification. ForeFlight Mobile Legends v12.6 and later! 4 Snow - Radar Intensity (dBZ) vs. Color Based on RGB values assigned to dBZ range(s) dBZ Internet Color1 ADS-B Color2,3,5 XM Color4 5 none shown 10 none shown 15 20 25 30 35 40 45 50 55 60 65 70 1. Colors are interpolated between levels when rendered on an image. 2. ADS-B (ie: FIS-B) NEXRAD radar is displayed with 6 intensity ranges. 3. FIS-B NEXRAD doesn't include precipitation type, so "Snow" is displayed at the same reflectivity colors as rain. See AIM Chapter 7: http://tfmlearning.fly.faa.gov/ publications/atpubs/aim/chap7/aim0701.html 4. Some dBZ intensity/color divisions do not fall exactly on 5 dBZ lines, so are shown as close as possible to specification. ForeFlight Mobile Legends v12.6 and later! 5 Four-color Radar - Radar Intensity (dBZ) vs. Color Based on RGB values assigned to dBZ range(s) dBZ Internet Color ADS-B Color SiriusXM Color1 5 none shown 10 none shown none shown 15 20 25 30 35 40 45 50 55 60 65 70 75 95 1. Baron Mobile Link/WXWorx radar does not display in 4-color mode. Only available with SiriuxXM when using the SXAR-1 receiver. ForeFlight Mobile Legends v12.6 and later! 6 Baron Mobile Link/WXWorx XM Radar Intensity (dBZ) vs. Color Based on RGB values assigned to dBZ range(s) dBZ Rain Mixed Rain/Snow Snow 5 none shown none shown none shown 10 15 20 25 30 35 40 45 50 55 60 65 70 75 none shown 95 none shown 1. Some Baron Mobile Link/WXWorx XM dBZ intensity/color divisions do not fall exactly on 5 dBZ lines, so are shown as close as possible to specification. ForeFlight Mobile Legends v12.6 and later! 7 Icing Legend (Internet & SXAR1) Icing Intensity Color Trace, Light Moderate Heavy, Severe SLD Threat (SXAR1 only) Note: SLD (supercooled large droplets) Threat indicates the potential presence of large droplets of sub-freezing liquid water, which present a more serious icing hazard than standard icing conditions. See this page for more information on SLD. ForeFlight Mobile Legends v12.6 and later! 8 Cloud Tops (ADS-B) Forecast Cloud Top Height (ft) Color Above 24000 Above 21000 Above 18000 Above 15000 Above 13500 Above 12000 Above 10500 Above 9000 Above 7500 Above 6000 Above 4500 Above 3000 Above 1500 Above 0 ForeFlight Mobile Legends v12.6 and later! 9 Turbulence Legends Internet & ADS-B Turbulence XM Turbulence EDR Turbulence Color Intensity Color Intensity 10 Light 20 Moderate 30 Severe 40 Extreme 50 60 70 80 90 Turbulence intensity is ultimately based on EDR (eddy dissipation rate), a measure of how quickly the atmosphere is releasing energy; however, how this numerical value translates into inflight turbulence intensity depends on a given aircraft’s weight. The internet turbulence layer provides an objective (forecast) measure of EDR which will need to be interpreted in the context of a given aircraft’s weight category to arrive at an actual turbulence intensity. The SXAR1 turbulence layer, on the other hand, assumes a medium aircraft weight category and provides actual turbulence intensity for aircraft in that category; smaller aircraft will experience more severe turbulence at a given intensity and larger aircraft will experience less severe turbulence. ForeFlight Mobile Legends v12.6 and later! 10 The following graphics correlating EDR with turbulence intensity for each weight category can be used as a rough guide: Light Aircraft (takeoff weight of 15,500 lbs or less) Medium Aircraft (takeoff weight of 15,501 to 299,999 lbs) Heavy Aircraft (takeoff weight of 300,000 lbs or more) ForeFlight Mobile Legends v12.6 and later! 11 XM Freezing Level The Freezing Level layer uses colored gradients (and when zoomed-in, altitudes in feet at the color borders) to depict the lowest altitude at which freezing and icing may occur across the continental U.S., southern Canada, and northern Mexico. Altitude (ft) SFC 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 14000 15000 16000 17000 18000 19000 ForeFlight Mobile Legends v12.6 and later! 12 XM Surface Visibility The XM Surface Visibility layer shows a near-term forecast of surface visibility using colors to indicate forecast surface visibilities ranging from 10 to 0 statute miles. Visibility (mi) 0 statute mi 0.25 statute mi 0.5 statute mi 0.75 statute mi 1.0 statute mi 1.5 statute mi 2 statute mi 3 statute mi 4 statute mi 5 statute mi 6 statute mi 7 statute mi 8 statute mi 9 statute mi 10 statute mi ForeFlight Mobile Legends v12.6 and later! 13 Surface Analysis Legend (Internet & SXAR1) Feature Symbol Isobars Pressure Labels High Pressure Centers Low Pressure Centers Cold Front Warm Front Occluded Front Stationary Front Trough Squall Line (XM only) Dry Line (XM only) ForeFlight Mobile Legends v12.6 and later! 14 Radar Legends (when from Internet) Lightning (in last 5 minutes) Mesocyclone activity (Vortex of rising , rotating air) Tornado Hail PIREP Legend Icing PIREPs (increasing severity) Turbulence PIREPs (increasing severity) Sky & Weather PIREP ForeFlight Mobile Legends v12.6 and later! 15 Enhanced Satellite The Enhanced Satellite layer uses a combination of visible and infrared satellite imagery to provide a global image of cloud formations. Visible satellite images are primarily used during daytime and are “enhanced” with infrared highlights for the highest cloud tops. During the night, when visible satellite images are not available, the layer relies entirely on infrared images. Shades of gray are used to represent the lowest-topped clouds; the darker the shade of gray, the lower the cloud tops. Above the lightest shades of gray you may see blueish colors representing still colder and higher tops. Above this, shades of yellow, orange and red represent the coldest and highest cloud tops. As the temperature of the atmosphere generally decreases with height, a pilot can get a pretty good idea which clouds are high-level and which are low-level based on the color or shades of gray depicted. Cold cloud tops are often indicative of active thunderstorms that can produce severe or extreme convective turbulence. One thing to note is that thick cirrus clouds at very high altitudes will also show up as very cold clouds even though they may not be associated with deep, moist convection. Most of the time these high cirrus clouds do not have the same cellular appearance as convective clouds and thus have very little variation in color. See the temperatures that correspond to different colors in the table on the next page. ForeFlight Mobile Legends v12.6 and later! 16 Based on RGB values assigned to temperature range(s) Temperature ºC Color Relative Cloud Top Height -83 Higher -75 -70 -65 -63 -54 -50.2 -50 -38 -28 +12 Lower ForeFlight Mobile Legends v12.6 and later! 17 Color IR Satellite Unlike the Enhanced Satellite layer, the Color IR Satellite layer relies solely on infrared satellite imagery to display global cloud coverage, and uses a more refined color scale to represent cloud top temperature. The IR Satellite layer is a close cousin of the static color IR satellite images found in the Imagery view. The static images show not only the temperature of the cloud tops using the same colors, but also the temperature of the surface of the earth. This can make it difficult to know where clouds exist and where the sky is clear. The main improvement of the Color IR Satellite layer over the static images is that it attempts to mask out regions where the sky is clear, showing the map background in those regions instead of the surface temperature. While this masking algorithm works a majority of the time, it can be difficult to get it right every single time simply using temperature alone. For example, anytime there’s a shallow low-topped stratus deck, the tops of the clouds may actually be slightly warmer than the surface of the earth courtesy of a surface-based temperature inversion.
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